290 



Common Science 



FIG. 159. The glass does not leak; the moisture on it comes from the air. 



413. We see our breath on cold days and not on warm days. 



414. The electric arc is exceedingly hot. 



415. Rock candy is made by hanging a string in a strong syrup 



left open to the air. 



416. Dishes in which candy has been made should be put to soak. 



417. Moisture gathers on eyeglasses when the wearer comes from 



a cold room into a warm one. 



418. Sprinkling the street on a hot day makes the air cool. 



419. You cannot see things in a dark room. 



420. Where air is rising there is likely to be rain. 



SECTION 45. Softening due to oil or water. 



Why does fog deaden a tennis racket ? 

 How does cold cream keep your face from becoming 

 chapped ? 



Let us now imagine that animal and plant substances 

 have suddenly lost their ability to be softened by oil or 

 water. 



